Pitman.



G. P. MIGHAELSEN.

PITMAH.

APPLICATION FILED 001'. 5, 1911.

1,125,863. Patented Jan.19,1915.

HE NORRIS PETERS c0. PHOTO'LlTHOn WASHING TON l)v C.

UNlTl-ED TATES CLAUS P. MIGI-IAELSEN, OF PENAWAVIA, WASHINGTON, ASSIGNOE 0F TWO-THIRDS TO JOHN N. PICKRELL, (3F COLFAX, WASHINGTON.

PITMAN.

messes.

Application filed October 5, 1911.

To all whom it may concern Be it lmown that I, CLAUs P. MICI-IAELSEN, a citizen of the United States, residing at Penawawa, in the county of VVhitlnan, State of Washington, have invented certain new and useful Improvements in Pitmen; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to an improvement in pitmen, especially adapted for use in connection with mowers for driving the sickle bar, although the invention can be employed with equal success in analogous arts, such as, for instance, binders, windmills, etc.

The principal object of this invention is to provide a pitman for the purpose described, which is of an improved construction, is composed of a minimum number of parts, and is therefore simple in construction, and is cheap to manufacture.

The above and additional objects are accomplished by such means as are illustrated in the accompanying drawings, described in the following specification, and then more particularly pointed out in the claims, which are appended hereto and form a part of this application.

With reference to the drawings, wherein there has been illustrated the preferred em-- bodiment of this invention as it is reduced to practice, and throughout the several views of which similar reference numerals designate corresponding parts, Figure 1 is a side elevation of a pitman constructed in accordance with my invention, the drive shaft being shown in cross section, Fig. 2 is a top plan view thereof, Fig. 3 is a detail sectional view taken on the line 3-3 of Fig. 2.

In the embodiment of my invention illustrated in the drawings, 1 have designed the various parts for application to a driving shaft 5, on which is keyed by a spline 6 an eccentric drum 7 of the well-known type. The drum 7 is equipped with a pair of side plates or flanges 8 which extend beyond its periphery and produce a circumferential channel within which the connecting yoke of the pitman is freely seated.

The connecting yoke consists in two sub stantially semicircular bands which, as indi cated at 9, are preferably formed of strap steel, although some other material may be Specification of Letters Patent.

Patented Jan. 19, 1915.

Serial No. 653,009.

employed if found desirable. The terminals of each of the semi-circular band members 9 are bent to form outwardly extending apertured lugs or cars, indicated at 10. When the two bands 9 are applied to the face of the drum, the apertures of the adjacent cars 10 are adapted to register so that connecting bolts 11 may be inserted through them for properly connecting the band sections and for effecting a connection between the two rods of the pitman with the yoke. It is obvious, of course, that nuts 12 may be threaded on the terminals of the bolts 11 for holding these members against withdrawal from the members 10.

The pitman is, as shown in Fig. 2 particularly, constructed in two sections or rods, each of which is formed from a length of strap metal, as indicated at 18. The terminals of these rods or sections 18 are formed with outwardly and angularly extending apertured lugs 19. The lugs 19 of one terminal of each of the members 18 are held in the proper relation to the metallic bands 9 by the bolts 11 in the manner hereinbefore explained. The lugs 19 of the other terminal of the pitman rods 18 are secured to a two-part bearing box 18. The bearing box 13 is, as stated, formed in two sections, each of which is provided with a substantially semi-circular opening 14 so that, when the two sections are mated, they will define a circular opening to receive the crank of the driven shaft. At the meeting edges of the two sections are formed the outwardly ex tending ears 15 which are apertured and receive a bolt 16, whereby they are held in assembled relation. It will also be noted that the bolts 16 receive the ears or lugs 19 of the members 18, and thus serve to hold the two-part bearing box 13 in the proper relation to the terminal of the pitman.

From the foregoing description, it will be readily appreciated that the rotation of the driving shaft 5 will, through the medium of the eccentric drum 7, reciprocate the piston rods 18 with the consequent reciprocation of the member 13. The member 13 may, of course, be attached to the crank of ticularly directed, is the fact that by manipulating the nuts 12, the degree of frictional engagement between the bands 9 and the eccentric drum 7 may be varied in accordance with the conditions under which the machine is operated. Inasmuch as the eccentric drum 7 and the bands 9 are in use adapted to move in opposite directions and in frictional contact to each other, it is necessary to provide some simple lubricating means, whereby lubricant may be applied to the meeting faces of the bands 9 and the drum 7. For this purpose, therefore, I have provided an oil cup. which, as shown in the drawings, is of the ordinary type, having a screw-threaded nipple which is threaded in a bore formed in one of the band members 9. A further advantage which is obtained by the particular construction of the eccentric yoke is the fact that either of the pitman rods 18 may be tightened to compensate for wear of the parts or the like. In accomplishing the tightening or loosening of either of the pitman rods 18, it is only necessary to unthread one of the nut members 12 and to thread the other nut farther on its bolt 11. Inasmuch as the terminals of the rods 18 are rigidly connected to the box 13, it is obvious that the threading or unthreading of the nuts 12 on the bolts 11 will act to tighten or loosen the desired rod.

In reduction to practice, it has been found that the form of this invention illustrated in the drawings, and referred to in the above description as the preferred embodiment, is the most etiicient and practical; yet realizing that the conditions concurrent with the adoption of this device will necessarily vary, it is desirable to emphasize the fact that various minor changes in details of construction, proportion and arrangement of parts may be resorted to, when required, without sacrificing any of the advantages of this invention, as defined in the appended claims.

What is claimed is:

1. A pitman including a pair of rods forming the body of the pitman and having their terminals bent to produce outwardly directed apertured ears, a bearing box rigidly connected to the ears at one terminal of the pitman body member, and a yoke connected to the other terminal of the pitman body member, whereby the pitman may be operatively connected to an eccentric drum, said yoke including a pair of substantially semicircular bands having outwardly directed apertured ears, each of said bands being of a length less than one-half the circumference of the drum to which the yoke is applied, bolts inserted through the ears of the rods and through the adjacent ears of the bands, and nuts threaded on the bolts, whereby the tension on either of the rod members may be varied and whereby the diameter of the yoke may be varied.

2. A pitman including a pair of rods forming the body of the pitman and having their terminals bent to produce outwardly directed apertured ears, a bearing box rigidly connected to the ears at one terminal of the pitman body member, said bearing box consisting of two detachably connected sections, each having outwardly directed apertured ears formed at its opposite sides, bolts passing through the mating ears of the bearing box sections and through the adjacent ears of the rod members, and a yoke connected to the other terminal of the pitman body member whereby the pitman may be operatively connected to an eccentric'drum, said yoke including a pair of substantially semi-circular bands having outwardly directed apertured ears, bolts inserted through the ears of the rods and through the adjacent ears of the bands, and nuts threaded on the bolts whereby the tension on either of the rod members may be varied and whereby the diameter of the yoke may be varied.

In testimony whereof, I aflix my signature, 1n presence of two witnesses.

CLAUS P. MICHAELSEN.

Witnesses:

J. E. Moons, T. S. BENTSON.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

